The concert is the culmination of ten weeks of rehearsals that started on Saturday, August 27, with around 80 young musicians from across the region.
All of the Scottish Borders high schools and many primary schools will be represented by these talented young instrumentalists.
They will play a wide ranging repertoire, with something to suit all musical tastes, from Leonard Bernstein and Tchaikovsky to the Village People and from Dutch Clog Dances to Katy Perry.
The orchestras are funded by Scottish Borders Council, with generous additional financial support from Borders Young Musicians (the PTA that listens).
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Tickets available at the door priced £6 (£4 concessions), concert starts at 3pm.